Technical Field
This invention relates to an apparatus for and method of conveying food slices. In particular, the invention relates to an apparatus for and method of conveying potato slices in the manufacture of potato chips.
Description of Related Art
In some food manufacturing processes, food slices are prepared which are required to be conveyed from a first apparatus to a second apparatus. A number of different conveying apparatus are well known in the art, such as conveyor belts, flumes, etc. In some apparatus and methods the slices may be conveyed in bulk or in a stacked or overlapped configuration. However, in other apparatus and methods the slices are required to be conveyed individually, or in a “singulated” configuration, with no or minimal overlap between adjacent slices. When the food slices are thin and have a significant degree of flexibility, there is an increased chance of inadvertent slice overlap because the slices are less likely to butt up against each other, which would tend to occur with thicker and more rigid slices. An example of such thin and flexible slices is potato slices which are prepared during the manufacture of potato chips, which have a typical thickness of less than 2.5 mm, such as from 1 to 1.5 mm, and, prior to frying, are highly flexible.
When conveying food slices from a first apparatus to a second apparatus, in some applications the product feed-out rate from the first apparatus is different from the product feed-in rate to the second apparatus. In some particular applications, it may be desired to increase the packing density of products on the conveyor between the first and second apparatus.
When the food products have a tendency to overlap, there may be a problem to achieve product singulation, by avoiding slice overlap, in combination with a high packing density of product on the conveyor, which may be required to achieve efficient production rates.
GB-A-2481272 discloses an apparatus for, and method of, producing potato chips in which potato slices are subjected to lipophilic conditioning of the potato slices, by immersing the potato slices in heated oil, prior to a microwave explosive dehydration step, in which the oil-treated potato slices are conveyed through a microwave apparatus. In the lipophilic conditioning step, the slices are conveyed in batches though an oil bath by a helical conveyor. Then the slices are flowed down a flume and excess oil is removed prior to depositing the slices onto the conveyor which transports the slices through a microwave apparatus. The slices exiting the flume are highly singulated. GB-A-2481468 discloses a specific flume construction for use in that process.
However, there is a problem in taking the input singulated product flow from the flume and converting that into a highly packed product flow through the microwave apparatus which provides a slice distribution on the microwave conveyor with a high packing density and negligible product overlap.
In the manufacturing process disclosed in GB-A-2481272, it is essential to achieve consistent slice singulation in order to avoid arcing during the microwave explosive dehydration step. Arcing would cause consequential degradation in product quality, such as browning, burning, fusing of slices, etc.
The challenge is to achieve such slice singulation, and avoiding slice overlap, in combination with a high packing density of the sliced products on the conveyor, which is essential to achieve efficient production rates.
GB-A-2481471 discloses an apparatus for separating food slices, such as potato slices used in the manufacturing process disclosed in GB-A-2481272, which are carried on a first conveyor and depositing the food slices in a separated configuration onto a second conveyor. That apparatus employs an assembly of a kick roller with air knives to separate the slices. Although the apparatus disclosed in GB-A-2481471 achieves satisfactory slice separation, there is a need for a simpler and more versatile technical solution to the achievement of the combination of slice separation and close packing on a conveyor.